In July this year, National Highways announced that it would use hydrogen to power some of the heavy construction machinery such as excavators and dump trucks on the Lower Thames Crossing project. The authority has put out a tender for the production and supply of hydrogen to the project which will replace one-third of the diesel required, in an estimated £50m contract.
Opposers of the scheme have been quick to point out that this will be a very expensive way to cut carbon – due to both the cost of producing green hydrogen and the cost of purchasing construction equipment that runs on hydrogen. Some have accused National Highways of green washing because only a portion of the diesel will be replaced.
But we are in a chicken-and-egg situation here. Until the demand for green hydrogen is there, the cost won’t come down, but with costs so high, who is going to opt for green hydrogen?
Often, when we talk about hydrogen and construction, we focus on equipment-related technology such as whether combustion engines or fuel cells are the right way ahead. Even bigger questions are raised when we look at how green hydrogen will be generated, stored and transported.
Green hydrogen is created from water by electrolysis, powered by renewable energy such as wind or solar power. Black, grey or brown hydrogen is derived from fossil fuels. So is blue hydrogen, the difference being that the carbon produced is somehow captured. The challenge is that currently green hydrogen is much more expensive than any of the other types of hydrogen, even blue hydrogen with its costly carbon capture element.
We also need to think about where all the renewable electricity is going to come from, how we can store it and what applications will get priority. There’s also the question of how we should prioritise the use of hydrogen. Would it be better deployed in decarbonising steel manufacture, for instance, rather than powering construction plant?
Thankfully, these many conundrums have not discouraged some construction plant manufacturers from pushing ahead with hydrogen technology. The Government made a great fanfare in February this year when it granted a special order to JCB to move its prototype hydrogen-powered backhoe loaders around on the roads. Having tested both fuel cell and combustion engine hydrogen technology, JCB thinks that the latter is the most pragmatic choice for now and is trialling it in various construction and agriculture machines.
At the end of July, Grant Schapps - then energy secretary - is reported to have challenged JCB to get its hydrogen-powered construction plant onto sites within the year while visiting the manufacturer in Derbyshire. The reports don’t say whether JCG chairman Lord Bamford challenged the Government to sort out the extensive hydrogen infrastructure needed to make that a viable proposition.
Elsewhere, contractors are experimenting with other types of plant too. In the Netherlands, which is arguably more progressive than the UK in its push to decarbonisation, Bam Infra Nederland announced last year that it had converted a paving machine to hydrogen from diesel. China’s Sany reported that it had produced prototype dumpers and mix trucks that ran on fuel cell technology in 2021. And 2022 saw Hyundai unveiling a hydrogen excavator, also based on fuel cells.
Meanwhile, we must also think about shorter-term solutions than hydrogen, which will reduce carbon emissions now while we sort out answers to some of the big questions outlined above. Some of Thermal Road Repairs’ R&D budget has gone into investigating alternative fuels and today our heaters can run on a combination of solar and biofuel or hydrogenated vegetable oil (HVO) – although the latter has come under fire recently in the UK due to concerns about its sustainability credentials.
JCB and others must be applauded for pursuing hydrogen technology, not least because of the magnitude of investment required. And we need clients, particularly public sector ones such as National Highways, to take a lead in order to prove the concept and hopefully start to ramp up demand.
The accusations of green washing levelled at the Lower Thames Crossing’s hydrogen plans don’t seem fair. Neither do suggestions that spending money on developing hydrogen technology won’t deliver value – in the widest sense of the word. We can all see where concentrating on capital costs only while ignoring carbon costs has got us so far…
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Thermal Road Repairs is a green technology company which supplies systems to improve the quality, cost and time efficiency of road repairs and paving – at a far lower environmental cost than traditional methods. It invests significantly in R&D, to create new technologies and to continuously improve existing ones.
Thermal Road Repairs: Decarbonising the asphalt repair industry.
High output. Low emission. Zero waste. Permanent solution.
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